[mgreenleaf]

I think it depends very much on the data being modelled.

Certain situations might call for a timestamp instead of a boolean, especially if it is a value that is only ever turned on once and never turned off, possibly `user_deactivated_at`; I do prefer having a bit field and a separate timestamp for things that can flip; and for a lot of use cases it is good to just have a full event stream implementation where you can construct the state at any point in time and you get events data combined with the timestamps.